Improvement in steam hoisting-machines



l. RUSHWURTH.

Steam Huisting-Machines. N0 l53,l18 I Patenfed 1u|y14,1824.

UNITED STATES JOHN RUSHWORTH, OF NEW YORK, N. Y.

IMPROVEMENT IN STEAM HOISTING-MACHINES.

Specification forming part of Letters Patent No. 153,118, dated July 14,1874; application Afiled January 30, 1874. v

To all whom it may concern:

Be it known that I, JOHN RUsHwoRTH, of the city, county, and State ofNew York, have invented a new and Improved Hoisting Apparatus; and I dohereby declare the following to be a full, clear, and exact descriptionthereof, which will enable those skilled inthe art to make and use thesame, reference being had to the accompanying drawing forming part ofthis specification, in which dra-wing- Figure l represents a sectionalside View ot' my invention. Fig. 2 is a plan or top view of the same.

Similar letters indicate corresponding parts.

This invention consists in the arrangement of a brauch exhaust-pipe,which connects with the steam-supply pipe ot' a steam-hoister, both thesteam-supply pipe and the branch eX- haust-pipe being supplied withstop-cocks in such a manner that, when the apparatus is used forlowering goods, or whenever the steam-piston is moved by the action otthe load suspended from the hoisting-drinn, the compressed air can beallowed to escape from the cylinder through the branch exhaust-pipe withmore or less rapidity, and the operation of lowering goods can beconducted with ease and facility.

In the drawing, the letter A designates a hoisting-drum, to which motionis imparted by a steam-piston, B, which is fitted and moves in acylinder, C. This cylinder is supplied with steam from a generator, D,through a steam-supply pipe, E, and the steam exhausts from the cylinderthrough the port c and the exhaust -pipe F, which may lead into thesmoke-chamber of the generator or in the open air. The steam-supply pipeE is provided with a stop-cock, b, and an additional exhaustpipe, G,branches oft' from that portion of the steam-pipe which is situatedbetween the stopcocl; b and the steam-chest or steam-cylinder. Thisbranch exhaust-pipe G may lead into the main exhaust-pipe F, or it maylead directly into the smoke-chamber or into the open atmosphere, and itis provided with a stop-cock, o. If the hoisting apparatus is used forraising goods, the stop-cock b in the steam-pipe is opened, thestop-cock c of the branch exhaust-pipe is closed, and, when steam entersthe cylinder through the port el and exhausts through the port cl', thepiston moves in the direction of arrow l; but, if the steam-cock I) isclosed and the apparatus is used for lowering goods, the piston isdriven by the weight ofthe load, and, when the slide-valve is in theposition shown in Fig. l, the piston moves in the direction ot' thearrow 2, and consequently, by said piston, air is sucked in through themain exhaust pipe and port cZ, and the air in front of the pistou isforced out through the port el into the steam-chest, from which it ispermitted to escape with more or less rapidity by opening the stop-cockc in the branch eX- haust-pipe G. By adjusting the stop-cock c the loadcan be lowered with more or less velocity.

It will be readily understood from this description that in my hoistingapparatus the operation of raising and lowering' goods can be governedsimply by means ofthe steamcock b and the stop-cock c in the branchexhaust-pipe.

What I claim as new, and desire to secure by Letters'Patent, is

In a steam hoisting apparatus, the branch exhaust-pipe G, in combinationwith the steampipe E, exhaust-pipe F, cocks c and b, cylinder C, andhoisting-drum A, substantially as and for the purpose set forth.

This specification signed by me this 24th day of January, 1874.

JOHN RUSHWORTH. Witnesses:

W. HAUFF, E. F. KASTENHUBER..

